Logarithmic linear relation between voice intensity and mean airflow rate under a constant fundamental frequency

Abstract

This paper reports on the piecewise linear relationship between voice intensity and mean airflow rate, both represented in logarithmic scale, under a constant fundamental frequency. For the experiment, each subject increased the voice intensity in steps of 2 dB, keeping fundamental frequency at a comfortable level. The same procedure was performed at several other pitch levels. As a result, we determined that three line segments are most appropriate to fit the data. Overall patterns for the three line approximations were examined, and it was found that S-shaped patterns were observed most frequently. The line segment in the medial intensity region had the largest slope value of the three line segments in the low, medial, and high intensity regions. This result reinforces the frequent appearance of S-shaped patterns in the data.